how to put one dimensional data to two dimensional array?

Hi, there.

I have multiple index text files. (ex, example1.txt, example2.txt, example3.txt, and so on...)

Each text file contains several columns (ex, 10 columns), and among them, I want to extract one specific column (ex, 6th) from each text file and put it into an array in order.

To do that,

I wrote this.

index_start = 1652; index_end = 1653;

for j = index_start:index_end

    data(j) = importdata(sprintf('example%d.txt', j)); 

    A = data(j).data(:,6);     

    end

But, it always returns one dimensional array (A) with the data from 6th column in the last index file (1653).

I believe there must be a solution.

Thanks in advance.

Answer 1

[Mischa Kim]

Lee, try something like

 A(:,jj - index_start + 1) = data(j).data(:,6);

This will put the first column that is read into the first column of A, the second column that is read into the second, and so on and so forth.

Just make sure that the column vectors all have the same size. Also, for large matrices A you might want to pre-allocate it, e.g., using the zeros command.

[Lee]

It works!!!

Thanks for the tip of pre-allocation as well!